Thursday, June 21, 2012

Arctic sea ice is melting nearly twice as fast as usual for June

I know it's only been a little while since my last Arctic sea ice update. Am I obsessed? Maybe...but that doesn't really matter...what matters is that things are currently happening FAST in the Arctic.

According to the good folks at NASA and the National Snow and Ice Data Center (NSIDC.org), Arctic Ocean sea ice cover changed dramatically over the past few weeks.

How far ahead of the historic baseline rate of sea ice melt are we? The map below (NSIDC.org) shows that ice melt near Alaska and eastern Russia is on track with the 1979-2000 averages, but sea ice melt is well ahead of schedule north of Scandinavia, around Svalbard, SW of Greenland, and in the Kara Sea (north of Russia).

The white area on the map shows the area of the Arctic Ocean that currently has at least 15% sea ice cover. The orange lines show the 1979-2000 historical sea ice cover on June 20th.

The data on this graph (courtesy of the NSIDC.org, and adapted buy me [lines and arrows]), though, was a real eye opener.

Figure description: The arrows #1 show the difference in sea ice cover between the 1979-2000 average and the 2012 cover at the beginning of June 2012. Arrow #3 shows the area melted during the first three weeks of June for the 1979-2000 average. Arrow #4 shows the area melted during the first three weeks of 2012, and arrow #2 shows the difference between the area of sea ice at the end of the three week period in 1979-2000 versus the ice cover area in 2012.

Historically, sea ice cover decreased from about 12.8 million km2 to 11.75 million km2 between 1 and 20 June, for a daily rate of sea ice melt of about 52,500 km2/day (see arrow #3 above). During the current year, however, sea ice cover decreased from 12.45 million km2 to 10.5 million km2 in the same time period, for a daily rate of sea ice melt of 97,500 km2/day (see arrow #4 above).

THIS MEANS THAT DURING THE PAST THREE WEEKS WE OBSERVED ARCTIC SEA ICE LOSS AT NEARLY DOUBLE THE HISTORIC RATE FOR THIS TIME PERIOD.

See the Table below for more data...if that sort of thing floats your boat...

1979-2000 Avg.

2012

Difference

1 June sea ice cover

12,800,000 km2

12,450,000 km2

350,000 km2

20 June sea ice cover

11,750,000 km2

10,500,000 km2

1,250,000 km2

Total Difference

1,050,000 km2

1,950,000 km2

855,000 km2

Rate of sea ice
loss

52,500 km2/day

97,500 km2/day

Does this mean that we are likely to see a new record sea ice melt in the Arctic IN 2012? It's hard to say, since weather conditions have the biggest effect on the rate of sea ice loss. We are, however, currently seeing record sea ice melt for June (so far), but not by much - see the graph below (NSIDC.org). The sea ice extent for this time period in 2010 and 2011 is similar, thought slightly higher than are seeing this year. If the 2012 ice melt stays on its current pace, there's a very good chance we could set a new record minimum sea ice extent (=sea ice melt) in the Arctic by September 2012.

It is important to note that sea ice can melt, reform, and get blown around, affecting the total area of the Arctic Ocean covered by sea ice. Only the coming days and weeks will determine whether we will see a new sea ice melt record.

Don't get me wrong...I get the impression that some people think that I LIKE that Arctic sea ice is melting. Nothing could be farther from the truth. I don't like it, but I don't reject valid observations just because I may not like what they show, and because this is something that is happening that can affect the entire global climate, I feel compelled to share what I know about it.

What can we do about the situation in the Arctic?

While I believe that every little bit helps, and that individual choices can have an impact, and at the risk sounding a bit of gloom, it is possible that we may be past the point where individual action will make a significant difference. I personally believe that we have reached a point where we must have governments pass stronger regulatory legislation limiting greenhouse gas emissions in order to make any meaningful progress toward any large-scale mitigation of climate change.

Here's hoping that at least the US Congress can get its act together and get to work on some meaningful environmental legislation! Please, oh please, oh please!